The linear motion bearing is widely used as industrial machine elements such as a table saddle for a machine tool, a slide face of a machining center or a carriage of a conveyor.
The linear motion bearing of the prior art is constructed, as shown in FIG. 6, to include: a track bed 10; a bearing body 20 of a metal placed on the track bed 10; a pair of side covers 30 and 30 of a synthetic resin fixed in abutment on the two end faces of the bearing body 20; a number of balls 40 interposed between the bearing body 20 and the track bed 10; and a not-shown retainer for preventing the balls 40 from coming out when the bearing body 20 is removed from the track bed 10.
In the linear motion bearing thus constructed, the side covers 30 are fixed by using screws 80 on the two end faces of the bearing body 20. Specifically, the side covers 30 of synthetic resin are formed with through holes 35 in their predetermined positions. Moreover, the metallic bearing body 20 is formed with tapped holes 25 in its corresponding positions. The screws are extended through the through holes 35 of the side covers 30 and fastened in the tapped holes 25 of the bearing body 20.
In recent years, the linear motion bearing described above is used in OA equipment or electric appliances, too. In these examples of use, the linear motion bearing is generally small-sized and compact.
The tapping operations of the holes 25 in the bearing body 20 becomes the more difficult together with the screw fastening operations as the linear motion bearing has the smaller size.
An object of the present invention is to solve the aforementioned problems of the prior art and to provide a side cover fixing structure capable of fixing the side covers simply and inexpensively on the body of a small-sized linear motion bearing.